Human error has been cited as a primary cause or contributing factor in disasters and accidents in many and diverse industries and fields. For example, traffic accidents involving vehicles are often attributed to human error and are one of the leading causes of injury and death in many developed countries. Similarly, distraction (e.g., mental distraction) of a worker affects performance at work and is one of the causes of workplace accidents.
Therefore, monitoring human operators, such as workers or drivers of vehicles, is an important component of accident analysis and prevention.
Safety systems to monitor a driver's steering, acceleration, braking and use of other controls, have been introduced into vehicles by several car companies.
Some safety systems use an infrared camera positioned on the vehicle's steering column. In these systems a camera must be correctly positioned at specific, often pre-determined locations and orientations so as to capture an image of the monitored human that can be analyzed.